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Short Stay Psychiatric Inpatient Admissions and Patient Reported Outcomes




Short Stay Psychiatric Inpatient Admissions and Patient Reported Outcomes

Sarah K Brown, DrPH and Rachel B Nowlin, MS, Mental Health Outcomes, LLC



Length of Psychiatric Inpatient Admissions

Over the last several decades, behavioral health care in the United States has changed tremendously, particularly by shifting from institutionalization toward more community-based services. Current inpatient behavioral health care focuses on crisis stabilization and treating patients in the least restrictive level of care, with limited bed space and financial constraints on the health care system overall (Glick; Lutterman). While in the 1980’s a four week stay might be considered a “short” stay, average inpatient admissions in the last decade are often 10 days or less (Glick; Shah; Lee; Zhang).

Unlike many medical conditions, there may not be a clear endpoint of what is expected during psychiatric inpatient treatment. Discharge goals vary based on each patient’s clinical presentation, and length of stay (LOS) may be driven by additional factors, including resources and operational considerations (Capdevielle; Crossley; Dimitri; Wolff). However, short stays are not necessarily associated with poorer patient outcomes (Babalola) and successful monitoring of patient outcomes regardless of LOS can grow our understanding of the impact of short stays.

Patient Reported Outcomes

Patient-reported outcomes (PRO) can be used as a regular part of clinical care in behavioral health to assess individual patients’ patterns of symptomology and treatment progress, or in aggregate as part of quality performance measurement. Clinical assessments often attempt to group patients as ill or not-ill, however in a short stay a patient may not realistically transition from an ill status to a well status. It may then seem tracking outcomes over a brief window of time is not possible using some clinical assessment instruments, but research has shown improvement can be measured even within a short stay (Frieri; Barbato).

Current LOS research largely focuses on predicting variations and outcomes of LOS, but there is a growing need for outcomes research that works within the more-restricted bounds of current average inpatient psychiatric LOS (7-10 days).  Thus, this article addresses the following: Can PRO provide an appropriate and meaningful way to measure patient improvement in a shortened LOS climate?


This research used an administrative clinical benchmarking dataset for acute inpatient, free-standing psychiatric hospitals. Data selected for analysis included discharges for two years (beginning July 2019), with a selected PRO measure at both admission and discharge.

The PROs selected for analysis are two reliable, valid, and appropriate measures for use in an adult inpatient setting (18+). The Behavior and Symptom Identification Scale (BASIS-32) is a 32-item self-report measure of a patient’s functioning, scored on a scale of 0 to 4, where higher scores indicate greater problems with functioning. The Patient Health Questionnaire (PHQ-9) is a 9-item self-report measure of a patient’s depression, scored on a scale of 0 to 27, where higher scores indicate more severe depression.

To measure patient improvement on either measure, we assessed the minimal change needed for an individual to have statistical and meaningful improvement (Eisen; Barbato; Jacobson). Standard error of measurement was calculated for the PRO; improvement was defined as change greater than one SEM, and percent improvement was the rate of all discharges that met that metric.


Patient reported clinical outcomes were available for 156,705 unique inpatient discharges at 142 facilities nationwide, with a mean length of stay of 7.7 days. While the average stay is a week, almost half of admissions were less than a week, with 12.6% being 1-3 days and 35.8% having 4-6 day LOS.

The typical admission was for a 35 year old (average age), male (51.9% of admissions), white and non-Hispanic (69.2% and 90.0% respectively). Primary diagnosis reported for admissions varied: 67.5% were categorized as mood disorder, 22.7% schizophrenia or other psychotic disorders, 5.4% substance use disorder, 3.7% as anxiety and other nonpsychotic disorders.

Examining PRO scores across discharges suggests there are differences in symptom severity and improvement for different lengths of stay. Rates of improvement differed with the shortest days having the least improvement compared to other lengths of stay. Furthermore, patients that demonstrated no change on PRO measures were more frequently in the shortest stay group (1-3 days).

Length of Stay
1-3 Days 4-6 Days 7-9 Days 10-12 Days 13 Days+
Distribution of LOS 12.6% 35.8% 29.4% 10.6% 11.6%
BASIS-32 (Discharges with scores) 12,475 40,055 34,896 12,355 12,191
Percent with Improvement
Improved 84% 85% 87% 86% 84%
No Change 13% 11% 9% 9% 11%
Got Worse 4% 4% 4% 5% 6%
Symptom Severity
Admission Severity Score 2.2 1.9 2.1 2.1 2.0
Discharge Severity Score 0.6 0.6 0.7 0.7 0.8
Change in Severity Score 1.6 1.3 1.4 1.4 1.3
PHQ-9 (Discharges with scores) 7,296 16,129 11,202 4,280 6,466
Percent with Improvement
Improved 65% 76% 79% 75% 75%
No Change 29% 19% 17% 20% 20%
Got Worse 5% 4% 4% 5% 6%
Symptom Severity
Admission Severity Score 12.1 14.0 14.5 13.4 13.9
Discharge Severity Score 4.2 4.2 4.2 4.3 5.1
Change in Severity Score 7.8 9.8 10.2 9.1 8.8



Analysis of this clinical benchmarking dataset adds an important examination of the length of inpatient admission to psychiatric hospitals, operating under the current framework of the United States behavioral health care system (Tulloch; Dimitri; Navarro). The data is consistent with recent literature, finding a mean length of stay 7.7 days (Tulloch; Zhang) and 12.6% stays were considered very short at 3 days or less.

The distribution of patient outcomes (most patients improve, but some decline or stay the same) suggests there is valuable data to be gathered through outcome measurement regardless of how brief the stay may be. Two different types of PRO were included: the BASIS-32 which is broader and assesses multiple domains of patient functioning while the PHQ-9 focuses specifically on depression symptoms. Since the BASIS-32 measures more general symptomology, changes might be detected more easily during a very short stay. Conversely, depression is a more slow-to-resolve condition and may be more difficult to track during a short stay (Fugger). Thus, results suggest measures which assess broad symptomatology are more robust at capturing change in the current inpatient environment when compared to disorder-specific measures.

Measuring change during a short stay requires awareness of the goal for a short stay. Returning to a general population baseline may not be possible in 3-5 days of treatment, but stabilization and/or transition to less restrictive care is achievable. For short stays, information gathered from admission and discharge PRO can provide a roadmap for focus during treatment as well as creating discharge plans that account for progress as well as areas where continued focus is needed. Given the reality of shorter stays, use of PRO can help ensure short stays are meeting the needs of patients (Glick) during their current admission.


The research question was framed with the assumption that short stays will continue to be the norm. Substantial patient improvement was demonstrated and patient reported outcomes are an appropriate and meaningful way to measure improvement when assessed using statistical methods beyond traditional clinical cutoffs.

While fewer patients achieve measurable improvement with short stays, there is still variation in improvement which can be meaningful for patients and providers. These findings suggest that no matter a patient’s LOS, measurable improvement can be achieved, supporting the use of PRO (particularly measures assessing broad symptomatology). Patient reported outcomes can be used to guide clinical care, track patient progress, and assess the quality performance of programs.


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